Window Security

Products for securing windows

Window locks

More than one third of burglars break in through a back window, so it is strongly recommended that you fit key-operated window locks to all ground floor windows, windows above garages or porches and any other window that can be reached easily from low wall or next to a drainpipe. If the opening part of the window is more than 2ft (600mm) in height or width, fit a second lock. This makes it harder to force the window open as it helps spread the load. Manufacturers generally supply short fixing screws in order to make them suitable for both light and heavy frames. If your frames are a heavier, thicker material, you can sometimes increase the strength of the lock by replacing the screws with longer ones - be careful not to get too close to the glass when using longer screws.

If you have an area where you are unhappy about the strength on the glass, Bradleys can fit a clear vinyl film to strengthen the glass, or if you are replacing the glass for any reason, use laminated glass to replace it with. Note also, how well the window does its job lock depends on the strength of the frame it's fitted to and this may also help you decide which type to use. Highly visible locks may deter some thieves - they will always try to avoid breaking glass if at all possible. Also, try to ensure that you've planned your home security with one or more escape routes in mind in the event of an emergency such as a fire.
You can find more on how to do this at www.firekills.gov.uk/escape

Locks for hinged (casement) timber windows

These locks are usually fitted opposite the hinge. Locks for hinged windows are usually sash to frame locks – meaning that half the lock is fitted to the window sash while the other is fitted to the frame. Most can be used only when the window is closed, but some types, called restrictors, can be locked with the window slightly open. They allow a bit of fresh air in but stop windows from being opened fully. Some restrictors are specifically designed to prevent children from falling out of open windows


Chubb 8K101 window lock Recommended casement locks include the Chubb 8K101 which although it requires you to turn the key a few times to tighten the 2 parts together, this also pulls in the window giving a good strong secure seal. This lock is also handy for windows which are slightly warped as it will pull the window inwards.


The Chubb 8001 mortice bolt is another good choice for this type of window. However, as the bolt fits into the window frame, please ensure that your window is sturdy enough to take bolt. A similar bolt for doors is available which uses the same key.


The Chubb 8K102, locks quickly and easily at the push of the button and takes just one turn of the key to unlock. By far the easiest in the range to use but one of the most expensive.


Finally, in the Chubb range is the 8K109. This is one of the budget locks in the Chubb range and not as secure as the others, but if price is a consideration, give this one a go.

Some window locks lock down the window's handle so you can't open the window without unlocking the handle. Usually, we don't recommend these as they rely entirely upon the handle itself being well fitted and secure in order to do their job.

Metal hinged windows

The Chubb 8K106 lock, requires a steady hand when drilling and like the 8K101 takes a few turns of the key to open and close, but again gives a good strong hold.

PVCu windows

There is not a lot of choice with locks for PVCu windows, but Chubb make the 8K123, which looks similar to, and works in the same way, as the 8K101 above.

Locks for sliding sash windows

Sash window is the term used for windows which slide up & down alongside each other. Sash window locks fasten the two window sashes together so they can't be opened form the outside. Flush locks fitted in the sash can't be seen from the outside, so won't provide a visual deterrent. You can buy the equivalent of restrictors for sash windows, too, called sash blockers. These let you open the window a few inches, but not fully, providing both security and ventilation.

The Chubb 8K114, is a bolt that locks the two window sashes together.

The Chubb WS1, is a sash blocker, allowing a sash window to be slightly open for ventilation, but not enough for someone to climb in. As it's partly concealed, you will need to chisel out holes in the window frame when you install it.

One other thing that can be considered for window security is the fitting of a security film to the glass. The film is virtually undetectable but will hold the glass in place against a brick or other object thrown at the glass.

The film comes in various formats - mirror, bronzed or coloured, and in varying thicknesses dependng upon its purpose. Its main use is to make glass safe in areas where people could fall against the glass and seriously injure themselves. The bronzed and coulored ranges are usually to help cut glare and heat coming into a building as well as security and safety.

The films can be fitted by the end user, but can be problematical - as with anything there is a knack to fitting and it may be better to ask our staff to install it for you.